Linehaul vs Fuel Surcharge vs Accessorials, With the Math

Updated 2026-08-10

A freight rate has three parts: linehaul is the price of moving the freight from A to B, the fuel surcharge is a separate, index-linked amount that absorbs diesel price movement, and accessorials are charges for work or delay outside the basic move.

Splitting them is not bookkeeping fussiness. Linehaul is negotiated, fuel surcharge is formulaic, and accessorials are conditional — three different arguments, and merging them means losing all three at once.

What each part covers

	Linehaul	Fuel surcharge	Accessorials
Covers	Truck, driver, and the miles	Diesel above an agreed baseline	Extra work, extra time, extra stops
Set by	Negotiation, load by load or by contract	A formula tied to a published index	A schedule of triggers and rates
Moves when	The market moves	Diesel moves, usually weekly	Something happens on the load
Where disputes come from	Rarely — the number is agreed up front	The index, the week, and the baseline	Almost always: proof and authorization

The fuel surcharge formula

The standard construction, and the one OOIDA publishes in its fuel surcharge calculator, is two steps:

(current diesel price − baseline price) ÷ assumed mpg = fuel surcharge per mile

OOIDA’s guidance uses about 6 mpg for a loaded tractor-trailer, and offers the rule of thumb of “one penny per mile for every 6-cent increase in diesel price.”

The current price comes from the U.S. Energy Information Administration’s weekly on-highway diesel series. As of the reading dated 2026-08-03, the national average was $5.348 per gallon (EIA, updated weekly).

Worked example, baseline $2.50 per gallon:

Assumed mpg	Calculation	Fuel surcharge
6.0	($5.348 − $2.50) ÷ 6.0	$0.475 per mile
6.5	($5.348 − $2.50) ÷ 6.5	$0.438 per mile
7.0	($5.348 − $2.50) ÷ 7.0	$0.407 per mile

Our calculation from the published EIA reading and stated mpg assumptions. The baseline is a contract term, not a published figure — $2.50 is used here only to show the arithmetic. See methodology.

Which index you pick is worth real money

The EIA publishes a national average and regional averages, and they diverge. From the same 2026-08-03 reading: West Coast $6.130, California $6.716, Midwest $5.262, Gulf Coast $5.141, against the national $5.348.

Run the same formula on a 500-mile load at 6 mpg with a $2.50 baseline:

Index used	Surcharge per mile	On 500 miles
Gulf Coast ($5.141)	$0.440	$220
National ($5.348)	$0.475	$237
West Coast ($6.130)	$0.605	$303

Same load, same formula, an $83 spread between the Gulf Coast and West Coast index. Which is why a fuel clause that just says “fuel surcharge per DOE index” is an unfinished clause. A finished one names four things:

Which index — national average, or a specific EIA region
Which week’s reading applies to which loads (the EIA posts weekly; say whether Monday’s number governs the week that follows)
The baseline price at which the surcharge is zero
The assumed mpg

Get those in writing on the rate confirmation or the master agreement and the fuel conversation stops happening.

A full quote, broken out

A 500-mile dry van move, one extra stop, two hours of detention at the receiver, and a lumper at delivery:

Line	Basis	Amount
Linehaul	Negotiated for the lane	$1,200.00
Fuel surcharge	500 mi × $0.475 (national index, $2.50 baseline, 6 mpg)	$237.50
Extra stop	Per rate con schedule	$75.00
Detention	2 hrs past free time, per rate con	$90.00
Lumper	Reimbursed at cost, receipt attached	$185.00
Total to the carrier		$1,787.50

Two things worth noticing. First, the lumper line is a pass-through, not revenue — if it silently becomes part of a “rate,” someone is eating it later. Second, linehaul plus fuel here is $1,437.50 over 500 miles, or $2.875 per mile all-in against ATRI’s published industry-average operating cost of $2.336 per mile in 2025 (ATRI) — before any deadhead the carrier ran to get there.

The accessorial list to price before you need it

Charges you did not agree in advance are charges you argue about after delivery. Have a rate for each of these in your rate confirmation template:

Detention, loading and unloading, with free time and a daily cap
TONU and layover
Extra stops (per stop, and whether it includes wait time)
Driver assist or driver count
Lumper handling and reimbursement
Liftgate, residential, limited access, inside delivery (mostly LTL — see FTL vs LTL vs partial)
Tarping, oversize permits, escorts (flatbed)
Reefer fuel, pre-cool, continuous run, temperature recorder
Redelivery, reconsignment, storage
Detention-to-layover conversion after a stated number of hours

FAQ

How is a fuel surcharge calculated? Current diesel price minus an agreed baseline, divided by an assumed mpg, giving a per-mile surcharge (OOIDA). The current price comes from the EIA’s weekly series; the baseline and mpg are contract terms you negotiate.

What diesel price should the surcharge use? Whichever the contract names — and it must name one. The EIA publishes a national average and regional averages weekly, and the spread between regions was over a dollar a gallon in the 2026-08-03 reading. National is simplest; a regional index is fairer on lanes that live in one region.

What is linehaul? The base charge for moving the freight between the stops, excluding fuel surcharge and accessorials. On truckload it is usually quoted as one flat number for the move, even when everyone discusses it in dollars per mile.

Should I quote one all-in number instead? Customers often ask for it, and it is fine as long as your own paperwork keeps the parts separate. If diesel moves 40 cents and your all-in number has no mechanism to move with it, you have written a fixed price on a variable cost.